It would seem that shmiras einayim must be fraught with negativity since we need to keep on nudging ourselves:
"Don't look!", "Keep your eyes down and never mind what you're missing out on!" But constraining unruly urges can be a bitter struggle because trying to suppress powerful desires is like squashing down a coiled spring that is gathering the strength to jump right back with more force than before.
The answer to this, says Rav Chaim Friedlander, ztz"l, is to focus on the benefits of guarding one's eyes. The struggle, then, is no longer between enjoying a certain pleasure and giving it up, but rather between choosing one pleasure in favor of another one. Sending ourselves positive messages and cultivating a positive attitude might be far more helpful. We could reiterate our basic premise that deep down we really want to stay inside the Torah's safety net and be clean and pure.
We're not seeking to be awash in momentary thrills; we choose to rise above that kind of thing. They leave long-term damage and have already caused untold havoc in enough areas. We'll go for the gold - true spiritual wealth and eternal bliss. This style of thinking is far more effective. We are no longer suppressing our basic desires. Taking pride in preserving one's purity by saying "no" to forbidden pleasures gives a marvelous boost to the morale. A spirited and upbeat attitude turns shmiras einayim into an informed preference as to how we wish to live, rather than a difficult sacrifice which drains our energy. By choosing a more positive attitude, it is no longer necessary to keep the palm pressed down so hard on that coiled spring of lust. The roaring fires of our unruly passions begin to behave themselves and to lose their edge. This is me, happy to march under the banner of shmiras einayim.
In that vein, the sefer "Veha'eir Eineinu" was written to spell out some of the wonderful benefits and rewards granted (in This World and the Next) for shmiras einayim - guarding one's eyes in our challenging times. It gives the reader clear guidance and tips and will help him regain his footing when he feels he is losing ground.
In itself, just learning about matters of purity will help us rein in and control our impulses. The Midrash (Nasso, 14:4) promises that whenever we truly toil over a particular Torah teaching, Hashem will remove from us the desire to commit that sin.
We get a kick-start by reminding ourselves that, moment-by-moment, our shmiras einayim is bringing immense satisfaction to Hashem. And the good news is that the real uphill struggle is only for the first bit. The Mesilas Yesharim assures us that kedusha starts off as effort, but then it comes to us as a reward. At first, it's work - following that, it is handed to us as a gift. Only the first struggles are so seriously tough.
The Chinuch writes that if you shut your eyes not to see evil once, it will make it easier to do so many more times. If we restrain ourselves now, we will rejoice in our lot forever after. The yetzer hara towers like a mountain. But as soon as we kick some of the old habits, the road ahead is surprisingly smoother, and all it takes is a slight but continuous input to keep us in the driver's seat.